/Engine/Plugins/Experimental/TextToSpeech/Source/TextToSpeech/Public/TextToSpeechEngineSubsystem.h
Returns true if a text to speech channel associated with a channel Id exists. Otherwise, the function returns false.
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(BlueprintCallable, Category=TextToSpeech) bool DoesChannelExist ( [FName](API\Runtime\Core\UObject\FName) InChannelId ) const